How it began
Carl Linnaeus, a Swedish botanist and taxonomist born in 1707 and known after his ennoblement as Carl von Linné, published Species Plantarum in two volumes in 1753. It listed more than 5,900 species of plants from around the world and gave each a unique two-word Latin name. It was the first botanical book to make consistent use of binomial nomenclature. He had begun earlier: his Systema Naturae of 1735, a pamphlet of 12 pages written when he was 28, set out the hierarchy of kingdom, class, order, genus and species.
How it works
Each species has a name of two Latin words. The first is the genus and the second identifies the species within it. In Species Plantarum the species word is printed in italics in the margin beside each entry. The genera themselves were defined separately: Linnaeus had published Genera Plantarum in 1737 with 935 genera and issued a new edition in 1754 with 1,105, so that the two books matched. Using Latin meant that local common names no longer caused confusion.
How it spread
Linnaeus extended the method to animals in the tenth edition of Systema Naturae, published in 1758 and 1759. In England one of the leading champions of Linnaean botanical classification was Erasmus Darwin of Lichfield, grandfather of Charles Darwin. Linnaeus had grouped plants by a so-called sexual system based on their reproductive parts. That classification did not last: Charles Darwin's work of 1859 brought down what was left of it. The naming system survived the change.
What lasted
Species Plantarum of 1753 is the formal starting point for botanical nomenclature. A plant that appeared in it with a binomial name has that name still, and no name published earlier counts. The tenth edition of Systema Naturae plays the same role for zoological nomenclature.
